- Rename expectDownloadOfMinRepo() to mockMinRepoDownload() to better describe what it does
- Move repoAdder.fetchRepository into expectMinRepoPreview() to reduce repetition
- Change some remnant example.com to min-v1.org
- Use explicit user-mirror-min-v1.org instead of example.com to make the intention clear
- Add comments to explain what's going on
- Make mockRepoDownload() configurable, to allow easier mocking of other repos in the futures (e.g., of mid and max)
See also fdroid/fdroidclient!1535
This clean up was prompted by the need to write a test for fdroid/fdroidclient!1530
otherwise the v1 repos still relying on them would not re-update and thus the DB miss their data. This can cause unintended breakage like apps not having a preferred repo.
If we are used to update the same repo at almost the same time, a race-condition can happen that tries to apply a diff to an already updated DB. We don't download anything while holding a DB transaction, so the download and check for the repo timestamp happens before we enter the transaction. However, we forgot to re-check the timestamp again within the transaction to be sure the DB state is still as expected.
The structure of the JSON (FeatureV2) and of our internal class AppManifest is different. The latter uses a list of strings instead of objects. The ReflectionDiffer didn't handle this different and was throwing an exception when diffing changing features.
However, the impact of this bug should be small as normally one version has an ID which is its SHA256 hash and thus its features shouldn't change over repo updates. Imaginable is erratic repo creation software though.
The default `simple` tokenzier config used in Room/SQLite3 FTS4 makes only ASCII characters case insensitive. The SQLite FTS3/4 doc [1] says:
> All uppercase characters within the ASCII range (Unicode codepoints less than 128), are transformed to their lowercase equivalents as part of the tokenization process. Thus, full-text queries are case-insensitive when using the simple tokenizer.
> The remove_diacritics option may be set to "0", "1" or "2". The default value is "1". If it is set to "1" or "2", then diacritics are removed from Latin script characters as described above. However, if it is set to "1", then diacritics are not removed in the fairly uncommon case where a single unicode codepoint is used to represent a character with more that one diacritic. [...] This is technically a bug, but cannot be fixed without creating backwards compatibility problems. If this option is set to "2", then diacritics are correctly removed from all Latin characters.
This change makes use of the intended behaviour by using the `unicode61` tokenizer with the `diacritics="0"` option to keep the behaviour similar to the current one. This replaces the previously used `simple` tokenizer. A migration is necessary to recreate the AppMetadataFts table to make use of the different tokenizer.
[1] https://www.sqlite.org/fts3.html#tokenizer
If an update was available from a disabled repo with a higher priority, the update from an enabled repo with a lower priority would not be offered as an update (i.e. returned by DbUpdateChecker#getUpdatableApps()).
